led driving circuit and its switching power supply controller
A technology of LED driving and switching power supply, which is applied in the direction of electric light source, electric lamp circuit layout, light source, etc., and can solve the problems of cost increase and circuit area increase
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
no. 1 example
[0219] refer to image 3 , The LED driving circuit of the first embodiment includes: a freewheeling diode D1 , an output capacitor C1 , an inductor L1 , a sampling resistor Rcs, a power supply capacitor C2 and a switching power supply controller 300 . The switching power supply controller 300 includes a power driving tube M1 , a grid zero-crossing detection circuit 301 , a comparator circuit 303 , a driving circuit 310 and a high-voltage starting power supply circuit 305 .
[0220] Wherein, the cathode of the freewheeling diode D1 is connected to the input voltage input terminal Vin to receive the input voltage; the first end of the output capacitor D1 is connected to the cathode of the freewheeling diode D1; the first end of the inductor L1 is connected to the anode of the freewheeling diode D1, The second end of the inductor L1 is connected to the second end of the output capacitor C1.
[0221] The drain of the power driving transistor M1 is connected to the first end of th...
no. 2 example
[0250] refer to Figure 8 , The LED driving circuit of the second embodiment is a floating structure, including: a freewheeling diode D1, an output capacitor C1, an inductor L1, a sampling resistor Rcs, a power supply capacitor C2 and a switching power supply controller 300 . The switching power supply controller 300 includes a power drive tube M1 , a gate zero-crossing detection circuit 301 , a comparator circuit 303 , a logic sum drive circuit 302 , an RS flip-flop 304 and a high-voltage start-up power supply circuit 305 .
[0251] In the second embodiment, the internal structure of the switching power supply controller 300 is the same as that of the first embodiment, the only difference is that the ground of the switching power supply controller 300 is a floating ground, which is different from the ground of the input voltage.
[0252] The connection mode of peripheral circuits other than the switching power supply controller 300 in the second embodiment is different from t...
no. 3 example
[0256] refer to Figure 9 , The LED driving circuit of the third embodiment is another floating structure, including: a freewheeling diode D1, an output capacitor C1, an inductor L1, a sampling resistor Rcs, a power supply capacitor C2 and a switching power supply controller 500 . The switching power supply controller 500 includes a power drive tube M1 , a gate zero-crossing detection circuit 501 , a comparator circuit 503 , a logic sum drive circuit 502 , an RS flip-flop 504 and a high-voltage start-up power supply circuit 505 .
[0257] In the third embodiment, the internal structure of the switching power supply controller 500 is the same as that of the first embodiment, the main difference is that the ground of the switching power supply controller 500 is a floating ground, which is different from the ground of the input voltage. Specifically, the high-voltage start-up power supply circuit 505 is connected to the floating ground through the power supply capacitor C2, and t...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More 


